From e39bbc8497b2c75466235341a4e13bcef37da5de Mon Sep 17 00:00:00 2001
From: CrazyMax <1951866+crazy-max@users.noreply.github.com>
Date: Wed, 10 Jan 2024 10:03:57 +0100
Subject: [PATCH] xx-apt: print-source-file flag

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>
---
 README.md         |  8 ++++++++
 src/test-apt.bats |  9 +++++++++
 src/xx-apt        | 14 ++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/README.md b/README.md
index a3af70bd..1a24b8a2 100644
--- a/README.md
+++ b/README.md
@@ -134,6 +134,14 @@ ARG TARGETPLATFORM
 RUN xx-apt-get install -y libc6-dev zlib1g-dev
 ```
 
+> [!NOTE]
+> `--print-source-file` flag can be used with `xx-apt` to print the path of the
+> main [Apt sources configuration file](https://manpages.debian.org/bookworm/apt/sources.list.5.en.html):
+> ```dockerfile
+> # debian
+> RUN xx-apt --print-source-file
+> ```
+
 Installing two meta-libraries, `xx-c-essentials`, `xx-cxx-essentials` is also allowed that expand the minimum necessary packages for either base image.
 
 ## `xx-verify` - Verifying compilation results
diff --git a/src/test-apt.bats b/src/test-apt.bats
index 4cde980a..8b0b9688 100755
--- a/src/test-apt.bats
+++ b/src/test-apt.bats
@@ -219,3 +219,12 @@ load 'assert'
   run apt show wget-notexist
   assert_failure
 }
+
+@test "print-source-file" {
+  run xx-apt --print-source-file
+  assert_success
+  assert_output --partial "/etc/apt/sources.list"
+
+  run test -e "$(xx-apt --print-source-file)"
+  assert_success
+}
diff --git a/src/xx-apt b/src/xx-apt
index 4b3e747a..bac13bbb 100755
--- a/src/xx-apt
+++ b/src/xx-apt
@@ -38,6 +38,20 @@ exitnolinux() {
   fi
 }
 
+n=$#
+for a in "$@"; do
+  if [ $# = $n ]; then set --; fi
+  case "$a" in
+    "--print-source-file")
+      aptsourcesfile
+      exit 0
+      ;;
+    *)
+      set -- "$@" "$a"
+      ;;
+  esac
+done
+
 # these are not supported yet
 case "${TARGETARCH}" in
   mips*)